SourceTree - Mac and Windows client for Mercurial and Git.
ForkHub - GitHub client for Android based on the abandoned official app
GitKraken - The intuitive, fast, and beautiful cross-platform Git client.
GITK - The GITK - Generalized Interface Tool Kit is a set of libraries, which form a (user) interface...
GitLab - Create, review and deploy code together with GitLab open source git repo management software | GitLab
Sublime Merge - Fast git client with integrated merge tool from the makers of Sublime Text